Floating offshore drilling vessels include system for compensating for movement of the vessel relative to a stationary well. One component of this system includes a marine riser tensioner. The tensioner applies a force on the drilling riser to manage differences in movement between the drilling riser and the vessel.
Marine riser tensioners on drilling vessels frequently experience load variations due to excessive friction on the tensioners. Conventional systems have attempted to measure the load variations with cylinder pressure transducers. However, the load variations often go unmeasured or undetected by cylinder pressure transducers, which result in mechanical failures elsewhere. For example, undetected load variations may lead to rod-seal-carrier-bolt failure due to excessive rod-to-rod seal-carrier friction loads. As a consequence, a large amount of drilling vessel non-productive time may be experienced while repairing failures that result from undetected load variations.
Furthermore, the data received using cylinder pressure transducers does not include information related to friction, nor does it fully describe normal tension variations during routine operations. The absence of this information and the means to observe it increases the difficulty in knowing when to service or exchange the cylinder.